This study will to determine the toxicity of combined recombinant interferon gamma and beta serine in patients with metastic non-small cell carcinoma of the lung; the response rate of this therapy as measured by disease-free survival and overall survival; the immune-modifying activity of this combined therapy as measured by induction of TNF; the expression of Class II HLA antigen on monocytes and the correlation of this to survival; the immune-modifying activity of this combined therapy as measured by induction of TNF; the expression of Class II HLA antigen on monocytes and the correlation of this to clinical response.